CuAl{sub 2} revisited: Composition, crystal structure, chemical bonding, compressibility and Raman spectroscopy
- Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany)
- Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstr. 1, 70569 Stuttgart (Germany)
The structure of CuAl{sub 2} is usually described as a framework of base condensed tetragonal antiprisms [CuAl{sub 8/4}]. The appropriate symmetry governed periodic nodal surface (PNS) divides the space of the structure into two labyrinths. All atoms are located in one labyrinth, whereas the second labyrinth seems to be 'empty'. The bonding of the CuAl{sub 2} structure was analyzed by the electron localization function (ELF), crystal orbital Hamiltonian population (COHP) analysis and Raman spectroscopy. From the ELF representation it is seen, that the 'empty' labyrinth is in fact the place of important covalent interactions. ELF, COHP in combination with high-pressure X-ray diffraction and Raman spectroscopy show that the CuAl{sub 2} structure is described best as a network built of interpenetrating graphite-like nets of three-bonded aluminum atoms with the copper atoms inside the tetragonal-antiprismatic cavities. - Graphical abstract: Atomic interactions in the crystal structure of the intermetallic compound CuAl{sub 2}: Three-bonded aluminum atoms form interpenetrating graphite-like nets. The copper atoms are located in the channels of aluminum network by means of three-center bonds. The bonding model is in agreement with the result of polarized Raman spectroscopy and high-pressure X-ray powder diffraction.
- OSTI ID:
- 20905302
- Journal Information:
- Journal of Solid State Chemistry, Vol. 179, Issue 6; Other Information: DOI: 10.1016/j.jssc.2006.03.006; PII: S0022-4596(06)00148-4; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
Similar Records
Metamagnetic transition in EuSe{sub 2}: A new, metastable binary rare-earth polychalcogenide
Phase relations and structural properties of the ternary narrow gap semiconductors Zn{sub 5}Sb{sub 4}In{sub 2-{delta}}({delta}=0.15) and Zn{sub 9}Sb{sub 6}In{sub 2}